1. Field of the Invention
The present invention relates generally to a robotic lawn mower using network sensors to identify the mowing areas, to define the mowing routes, and to program the mowing routes and patterns. The invention utilizes ultrasonic and RF devices together to identify the mowing areas and to track the position of the robotic lawn mower. Based on the invention, users can define the mowing sequences of the mowing areas, identify the boundary of mowing areas, and program the mowing routes. The control of the robotic lawn mower may be wireless and users may monitor and control the robotic lawn mower with a computer, a cell phone, or a tablet through wireless network, a WIFI, or an internet.
2. Description of the Related Art
With the invention of robotic lawn mower, people now can use it to do the lawn work and therefore save the time and energy for other things. A robotic lawn mower is an autonomous robot used to cut lawn grass. A typical robotic lawn mower requires the users to set up a wire at the lawn border to enclose the grass area to be mowed. The robotic lawn mower may detect the electromagnetic signal from the wire when it is near the border so as not to travel outside the enclosing area. In some applications, the robotic lawn mower may follow the wire back to the docking station for battery recharging. Robotic lawn mower can be quite sophisticated equipped with sensors to detect if there is a rain and to detect grass and non-grass areas and some models can control the blade speed based on grass height and move in spiral pattern when longer grass is found.
However, the existing robotic lawn mowers in the market, although with a microcontroller or a CPU embedded on them, are still not smart enough to allow users to use it at different lawns, to vary the mowing areas, to identify mower's position with respect to lawn border, and to control and monitor the mowing route precisely no matter whether the mower is near the border or in the middle of the lawn. For example, users may want to mow his or her house's lawn yard today, but tomorrow would like to help mow neighbor's lawn. The setup wire at neighbor's yard, if not impossible, would be very impractical. If user is a gardener, the person will definitely need to mow different lawns which have different landscapes and are at different locations, and the setup of the wires will become extremely difficult and time consuming Another situation is that users may want to mow a specific area of the lawn today and to mow another specific area of the lawn tomorrow, and users may like to mow several areas of lawn following a predetermined route or path. For these regards, a smart robotic lawn mowing system which is able to identify the lawn areas, to vary the mowing areas flexibly, and to track the position of the mower during its operation at any time is needed. Another application is that users may want to monitor and to modify the settings of mowing through a network or an internet. The invention here is to address these kinds of needs.
From the point of energy saving, a robotic lawn mower which is able to mow the lawn yard smartly is important. A smart mowing scheme is able to cover the entire lawn area but not to keep mowing the same spots repeatedly. The available existing robotic lawn mower in the market are not equipped with network sensors, and therefore, they may either keep mowing some spots repeatedly or are not able to cover all the lawn areas without missing spots, and this is currently a common disadvantage of the available robotic lawn mower products in the industry. The present invention, smart robotic lawn mower with network sensors, is able to control the mowing route, to avoid the repetition of the mowing at the same spots, and to identify the position of robotic lawn mower inside the mowing areas. With network sensors, the robotic lawn mower is able to cover the spots that might be missed when using the traditional robotic lawn mower.
In this application, a smart robotic lawn mowing system allows users to freely use it at different lawns and at different areas of a lawn, is disclosed. The core of the invention is to place the network sensors, which are the ultrasonic and RF devices, in the lawn yard, and on the robotic lawn mower. The ultrasonic and RF devices in this application are referred as the network sensors because they are coupled together for the mowing work. The application is to place ultrasonic transmitter and RF device on the robotic lawn mower, and to place ultrasonic receiver and RF device on the boundary stands. The boundary stands here refer to the devices allowing the ultrasonic and RF devices to be placed on them, and they may be populated at the peripheral, inside, or outside of a lawn area. The devices on the mower will communicate with the devices on the boundary stands. For practical applications, the boundary stands may be a fence, a post, a solar light, a wood stick, or any other similar entities allowing the ultrasonic and RF devices to be mounted on. The popular solar lamps, populating in the yards near the houses, are a good example for the placement of the network sensors. Ideally, the boundary stands shall be flexible to be set up, and they shall be able to be put on or removed easily, and portable to be moved to any different lawns or to different areas in the lawn yard. The ultrasonic transmitter on the robotic lawn mower is to transmit an ultrasonic wave toward the boundary stands located at various positions, and the RF device on the robotic lawn mower is to receive the RF signals from the boundary stands, and to transmit RF signals toward boundary stands. The ultrasonic receivers on the boundary stands are to receive the ultrasonic waves from the robotic lawn mower, and after the receiving the ultrasonic wave from the mower, each boundary stand will transmit a RF signal back to the robotic lawn mower to notify the mower the relative distance in between boundary stand and robotic lawn mower. For this situation, the RF device on the boundary stand may function as transmitter.
With the network sensors, the robotic lawn mower system will firstly define the mowing area based on an algorithm. After that, the robotic lawn mower may start to mow a lawn, and the mowing system will track the position of the robotic lawn mower at any time during its mowing operation. A mowing route is then either automatically programmed or predetermined and the robotic lawn mower may mow a lawn yard with designated schemes. With this invention, the mowing route and pattern may be controlled, monitored, and modified by users at either local or remote sites.